Induction of Labor in Primigravid Term Pregnancy with Misoprostol or Dinoprostone: A Comparative Study

Objective The objective of this study was to compare the effectiveness of vaginally administered misoprostol to that of vaginally administered dinoprostone at six-hour intervals in a well-homogenized cohort of full-term, nulliparous women with an unfavorable cervix and without any pregnancy complications. Materials and methods A cohort of 100 nulliparous women at more than 40 weeks of gestation was included in this study. The primary outcomes to be measured were induction to delivery interval and incidence of vaginal births within 12 and 24 hours. Neonatal intensive care unit admissions for poor neonatal outcomes and obstetrical complications were secondary outcomes. Results A significant reduction in the induction to delivery interval was observed in the misoprostol group as compared to the dinoprostone group (10.2 +/- 0.8 vs. 16.5 +/- 0.7, p < 0.001). More women in the misoprostol group delivered within 12 hours as compared to the dinoprostone group (30 [60%] vs. 17 [34%], p < 0.001) and within 24 hours (48 [96%] vs. 39 [78%], p < 0.05). In the misoprostol group, spontaneous rupture of the membranes occurred more frequently (46 [92%] vs. 35 [70%], p < 0.05) with less need for oxytocin augmentation during labor (14% vs. 30%, p < 0.05). A significant reduction in additional dose requirement (7.5% vs. 22%, p < 0.05) and a lower rate of Caesarean section was observed in the misoprostol group (6% vs. 24%, p < 0.04). A statistically insignificant low Apgar score was noted in the dinoprostone group compared to the misoprostol group. Conclusion Vaginally administered misoprostol is more effective than vaginally administered dinoprostone at six-hour intervals in nulliparous women beyond 40 weeks of gestation without pregnancy complications.